Surface area for gaseous exchange decreases
Excessive mucus is secreted by the epithelium
Airway block making breathing difficult
None of the above
Alveoli is well supplied with blood capillaries.
Alveoli walls is one cell thick which increase the rate of diffusion of gases.
A thin film of moisture covering the surface of the alveolus allows membranes to slide over each other easily during breathing.
Numerous alveoli help increase surface area to volume ratio facilitates exchange of gases.
C-shaped rings of cartilage are specialized structures of the trachea
Glands cells secreting mucus help trap dust particle in the trachea
Cilia in the trachea helps in breathing, to sweep air into the lungs and
Heart is found in the thoracic cavity
Diaphragm contracts and flattens
Inhalation & Exhalation
Difference in pressure
External intercostal muscles contract and internal intercostal muscles relax
Only diaphragm, intercostal muscles and sternum, is involved in inhalation and exhalation
During inhalation, external intercostal muscles relax and internal intercostal muscles contract.
Sternum move upward and forward exhalation.
Changes of the volume of cavity are workings of only the intercostal muscles and diaphragm.
One cell thick
Have an iron-containing structure
Trachea, Larynx, Bronchus
Larynx, Trachea, Pharynx
Pharynx, Larynx, Trachea
Trachea, Larynx, Pharynx
The amount of oxygen in inspired air different from expired air
The water content in inspired air different from expired air
Is temperature of inspired air different from expired air
The amount of carbon dioxide in inspired air different from expired air
Tar is a additive drug found in tobacco.
Number of cigarettes smoked per day is indirectly proportional with the risk of lung cancer
Carbon monoxide in tobacco increase the risk of fatty deposits in walls of arteries.
None of the above